Fabrication of high-performance, low-temperature solution processed amorphous indium oxide thin-film transistors using a volatile nitrate precursor

Abstract

In this study, we fabricate amorphous indium oxide thin film transistors (TFTs) on a display glass substrate at various annealing temperatures from 200 °C to 300 °C. Using a volatile nitrate precursor, we were able to fabricate TFTs with excellent device performance within this annealing temperature range. Amorphous In₂O₃ films could be obtained by carefully controlling the film thickness and annealing temperature. TFTs based on amorphous In₂O₃ channel layers with an average mobility as high as 7.5 cm² V⁻¹ s⁻¹, an I_on/I_off ratio of 10⁷, and V_on = −5 V could be fabricated at 300 °C annealing temperature in air. The devices prepared at 200 °C still exhibit transistor characteristics with an average mobility of 0.04 cm² V⁻¹ s⁻¹, an I_on/I_off ratio of 10⁵, and V_on = 0 V. The temperature effects on the device performances are elucidated based on X-ray photoelectron spectroscopy and thermal gravimetric analysis characterization results of precursors and the resulting amorphous In₂O₃ thin films.